IMS has been around since 1996 but does not dominate the IFE market.
My guess is that WENCOR bought IMS because
1: it was cheap (right time, right place with the digEplayer already dominating the portable market in short order with 13 airlines onboard and IMS could read the writing on the wall with the digEsystem already in talks with several airlines.
2: they now own their technology
3: they instantly have access to their business contacts/distribution channels, marketing and sales forces, thus quickening WENCOR`s time to market to jump start this relatively new IFE wing of WENCOR, which could likely become a major source of revenue for them.